Research

Mixed

Supplementation with commercially available leucine metabolites (α-HICA, HMB-FA, or HMB-Ca) does not enhance resistance training-induced gains in muscle thickness, strength, or power in young, moderately trained men consuming a high-protein diet.

If you are a young, moderately trained man eating enough protein and training consistently, taking HMB or α-HICA will not give you better muscles or strength than if you just took a placebo. Focus on your training and diet instead of spending money on these supplements.

GoodRefutesHIGH confidence
No leucine metabolite resulted in any ergogenic effects on any outcome variable. Supplementation with leucine metabolites – α-HICA, HMB-FA, or HMB-Ca – is not a supplementation strategy that improves muscle growth and strength development in young adult men.
Filipe J. Teixeira et al. · Medicine & Science in Sports & Exercise · 2018

Why this rating

Double-blind, randomized, placebo-controlled trial with adequate sample size and rigorous methodology, though limited to young men.

Source

Leucine Metabolites Do Not Enhance Training-induced Performance or Muscle Thickness

Filipe J. Teixeira et al. · Medicine & Science in Sports & Exercise · 2018

DOI 10.1249/mss.0000000000001754

rct · n=40Cited 33×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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